tor, 2004-04-08 kl. 15:30 skrev Lars E. D. Jensen:
> Hej
>
> Min server har 2 GB ram installeret, men Debian "opdager" kun 1 GB ram.
> Bios fortæller, at der er 2 GB ram installeret.
>
> Hvad kan årsagen være til dette?
Tjek din indstilling af CONFIG_NOHIGHMEM i din kerne. Du finder den
under "Processor type and features":
│ Linux can use up to 64 Gigabytes of physical memory on x86 systems. │
│ However, the address space of 32-bit x86 processors is only 4 │
│ Gigabytes large. That means that, if you have a large amount of │
│ physical memory, not all of it can be "permanently mapped" by the │
│ kernel. The physical memory that's not permanently mapped is called │
│ "high memory". │
│ │
│ If you are compiling a kernel which will never run on a machine with │
│ more than 960 megabytes of total physical RAM, answer "off" here (defau │
│ choice and suitable for most users). This will result in a "3GB/1GB" │
│ split: 3GB are mapped so that each process sees a 3GB virtual memory │
│ space and the remaining part of the 4GB virtual memory space is used │
│ by the kernel to permanently map as much physical memory as │
│ possible.
│ If more than 4 Gigabytes is used then answer "64GB" here. This │
│ selection turns Intel PAE (Physical Address Extension) mode on. │
│ PAE implements 3-level paging on IA32 processors. PAE is fully │
│ supported by Linux, PAE mode is implemented on all recent Intel │
│ processors (Pentium Pro and better). NOTE: If you say "64GB" here, │
│ then the kernel will not boot on CPUs that don't support PAE! │
│ │
│ The actual amount of total physical memory will either be auto │
│ detected or can be forced by using a kernel command line option such │
│ as "mem=256M". (Try "man bootparam" or see the documentation of your │
│ boot loader (grub, lilo or loadlin) about how to pass options to the │
│ kernel at boot time.) │
│ │
│ If unsure, say "off".
--
Claus Hindsgaul <claus_h@image.dk>